GE D90 Plus - Page 300

290 D90
PLUS
LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
GROUPED PROTECTION ELEMENTS CHAPTER 7: PROTECTION
Figure 250: Wattmetric characteristic angle response
Power Pickup Delay
Range: 0.00 to 600.00 seconds in steps of 0.01
Default: 0.20 seconds
This setting specifies a definite time delay before the inverse time characteristic is
activated. If the curve selection is set as “Definite Time,” the element operates after this
security time delay. If the curve selection is “Inverse” or one of the FlexCurves, the
element uses both the definite and inverse time timers simultaneously. The definite time
timer, specified by this setting, is used and when expires it releases the inverse time
timer for operation (torque control).
Curve
Range: Definite Time, Inverse, FlexCurve A, FlexCurve B, FlexCurve C, FlexCurve D
Default: Definite Time
This setting selects one of three methods to delay operate signal once all conditions are
met to discriminate fault direction. The “Definite Time” selection allows for a fixed time
delay defined by the
Power Pickup Delay setting.
The “Inverse” selection allows for inverse time characteristics delay defined by the
following formula:
Eq. 38
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